MELISSA BLOCK, HOST:
The investigation continues into Malaysia Airlines Flight 370, with few clues, an abundance of theories and a widening search area. The plane that disappeared was a Boeing 777, regarded as one of the safest in the industry. So what could have gone wrong? Well, leaving aside human action, one scenario is a catastrophic electrical failure of all systems.
Another is decompression of the aircraft. And we asked airline pilot Patrick Smith to explain that. He's author of the book "Cockpit Confidential." Smith starts with this: Planes are pressurized so occupants can breathe without the need for supplemental oxygen.
PATRICK SMITH: Now, if there is a hole in the airplane the pressure leaks out. And sometimes that can happen very rapidly or even explosively. Now, a run-of-the-mill depressurization, even a rapid or explosive depressurization, is perfectly survivable in most cases, assuming the crew does what it's trained to do.
BLOCK: What are you trained to do in a decompression situation?
SMITH: Well, it depends somewhat on the circumstances. But the gist of it is to descend the aircraft to an altitude where supplemental oxygen is not necessary. And the terminology will differ airline to airline, but we called it an emergency descent. And you configure the aircraft so that you're driving down at a very high rate of speed.
It's something I actually had to do in real life once as an airline pilot. And it sounds dramatic. It sounds scary to people. But in practice it was a relatively painless exercise. I describe it in the book somewhat in way more detail. But there were actually people in the aircraft who didn't realize we had done it.
BLOCK: Mr. Smith, as a pilot, can you help us understand why there wouldn't be a distress call from this aircraft?
SMITH: Well, normally if there is any sort of emergency or urgency on an airplane, the crew will deal with the situation before communicating. Communicating really takes a backseat and that's the way pilots are trained. There's an adage, as much as I hate aviation adages. It's: aviate, navigate, communicate, in that order where priority is always what's right there on the aircraft.
BLOCK: As you've talked to other pilots over the past week, what's that conversation like? What are people saying about this disappearance?
SMITH: Well, I think pilots by nature don't like to speculate a lot. And that's important here, I say on the air...
(LAUGHTER)
SMITH: ...speculating crazily. But, you know, because in these situations historically, you know, what comes out early on after a clash almost always turns out to be either incomplete or completely off base. You know, further to that point, what I hope doesn't happen with this accident is I hope it doesn't undermine the fact that air travel in 2014 is exceptionally safe as it is. Last year, for example, was the safest year in the entire history of commercial aviation.
You know, maybe we'll never get to the bottom of it. But, you know, the truth also is that flying is going to remain very safe and we're never going to be 100 percent safe.
BLOCK: Well, from a safety perspective, you absolutely would want to figure out what happened to this plane, right? If it is something that hasn't been seen before, you want to get to the bottom that.
SMITH: Oh, of course, needless to say. And that's what's fascinating about where we are in this story right now, because it's moved from being a story about a presumed airplane crash to just a mystery story. Because really the question here isn't where is the plane, it's what happened to the plane.
BLOCK: Patrick Smith, thanks so much for talking with us.
SMITH: Anytime, thank you.
BLOCK: Patrick Smith is author of the book "Cockpit Confidential," he runs a website Ask The Pilot.
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ROBERT SIEGEL, HOST:
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